The role of exercise in the fight against COVID19.
We all know that personal hygiene and social distancing are our primary weapons against this invisible killer right now.
But what of the role of exercise?
This virus is new. We have never encountered it before. Therefore evidence is sadly lacking. But let’s take a look at what we do know with regards to exercise, immune function and response to viral infections.
Exercise, in the right dosages, boosts immune function, improves immune response to vaccination and lowers chronic low grade inflammation. This chronic low grade inflammation is now being heavily linked to major modern disease such as cancer, diabetes, cardiovascular disease and even obesity. Do you recognise any COVID19 red flag issues there?
We also know self-isolation can have negative implications on mental as well as physical wellbeing. The main culprit being increasing levels of stress which elevates stress hormones and inflammation in the body. If left unchecked, this can markedly hamper our immune function over time.
So what of the role of exercise on COVID 19?
Good question! Well alongside our primary weapons, we simply NEED our immune systems firing on all cylinders. We know that cardiovascular and cardiorespiratory exercise (in the right doses) acts like a supercharger on our immune system.
After this type of exercise, stress hormone levels considerably lower, inflammation is dialled down and our immune system can get to work patrolling and safeguarding key areas of the body that COVID19 invades (the lungs and throat!).
Although this is a novel virus so there is no data on how exercise can directly protect us from it, I think a common sense perspective can potentially be adopted here. One that would liken fitter individuals, with higher functioning immune systems as having “money in the bank”, whilst individuals who are more sedentary as not being so “immune affluent”.
Should either party (god forbid) come across this awful virus, one could potentially assume the fitter party as having a head start in the race for life. Now, I know this is purely theoretical. I am also acutely aware that’s not how evidence-based practice works.
So let’s look at data that POTENTIALLY supports this theory.
Firstly, we know from studies in Illinois that regular, moderate intensity exercise protected mice from death from influenza based viruses (1). We also know that moderate intensity exercise protects human hosts from a large number of viruses (including viruses that fall under the coronavirus umbrella) whereas more prolonged or intense exercise does not appear to offer the same protection, even increasing risk of morbidity and mortality in certain instances (2, 3).
Additionally, studies on astronauts have clearly demonstrated that the astronauts who travelled into space with higher levels of conditioning, were far less likely to suffer the effects of viral problems than their counterparts with lesser levels of conditioning (4).
Another highly pertinent article states that regular physical activity reduces the risk of a person contracting viral or bacterial infections. This is due to enhancing the immune systems ability to regulate itself. Therefore, exercise regimes should be maintained and prioritised because they have the ability to improve immune competency (5). Sorry had to quote a fellow Turner!
So what does all of this mean?
Now obviously this is indirect data but it is the closest thing we have so it still needs to be considered highly relevant! Obviously the best way to combat COVID19 at present (until more is known) is to prevent exposure. This is why personal hygiene and social distancing are so, so important!
We cannot ignore the closest thing we have to evidence however. That is that exercise, in particular, moderate intensity exercise, does clearly demonstrate the ability to significantly boost immune function. Additionally it’s ability to improve resiliency to viral infection and positively affect the ability to fight back when infected cannot simply be ignored.
Conversely, in such times, we need to take into consideration the body of evidence that suggests more prolonged or intensive exercise may potentially negatively impact upon our resiliency against viral infections.
Put simply, we cannot underestimate the role physical activity may have in the fightback against COVID19. Moderate intensity exercise has proven it can increase immune function, lower stress, reduce inflammation and assist with the negative effects of isolation.
Should we all be prioritising moderate intensity exercise within our daily exercise regimes in such unprecedented times?
1) Martin SA, Pence BD, Woods JA. Exercise and respiratory tract viral infections. Exerc Sport Sci Rev. 2009;37(4):157–164.
2) Heath GW, Ford ES, Craven TE, et al. Exercise and the incidence of upper respiratory tract infections. Med Sci Sports Exerc. 1991; 23 (2): 152–7.
3 )Wong CM, Lai HK, Ou CQ, et al. Is exercise protective against influenza-associated mortality? PLoS ONE. 2008; 3 (5) :e2108.
4) Agha, NH, Mehta, SK, Rooney, BV, et al. Exercise as a countermeasure for latent viral reactivation during long duration space flight. The FASEB Journal. 2020; (34): 2869– 2881.
5) Campbell, J. P., & Turner, J. E. Debunking the myth of exercise-induced immune suppression: redefining the impact of exercise on immunological health across the lifespan. Frontiers in immunology. 2018; 9, 648.